1.80.2 FloatQ class: characterization

decimalDigits

Return the number of decimal digits of precision for a FloatQ.
Technically, if P is the precision for the representation, then
the decimal precision Q is the maximum number of decimal digits
such that any floating point number with Q base 10 digits can be
rounded to a floating point number with P base 2 digits and back
again, without change to the Q decimal digits.